Several of the readings came from the lecture notes on Intensional Semantics:
[Intensional Semantics] = von Fintel, Kai, and Irene Heim. Lecture notes. "Intensional Semantics." http://kaivonfintel.org/teaching/. (PDF)
Interspersed between these chapters were papers, presentations, and working papers. The readings were covered approximately in the order listed.
"Beginnings of Intensional Semantics." Chapter 1 in [Intensional Semantics].
See the summary tables on p. 128. The entire thesis is also worth a look:
Nauze, Fabrice. "Modality in Typological Perspective." PhD diss., Universiteit van Amsterdam, 2008. (PDF - 1.9MB)
"Propositional Attitudes." Chapter 2 in [Intensional Semantics].
"Modality." Chapter 3 in [Intensional Semantics].
"Conditionals." Chapter 4 in [Intensional Semantics].
Kusumoto, Kiyomi. "Issues in Tense Semantics." Chapter 1 in "Tense in Embedded Contexts." PhD diss., University of Massachusetts, Amherst, 1999.
Portner, Paul. "The Progressive in Modal Semantics." Language 74, no. 4 (December 1998): 760-787.
Kusumoto, Kyomi. "On the Quantification over Times in Natural Language." Natural Language Semantics 13, no. 4 (December 2005): 317-357.
Iatridou, Sabine, Elean Anagnostopoulou, and Roumyana Izvorski. "Observations about the Form and Meaning of the Perfect." In Perfect Explorations. Edited by Artemis Alexiadou, Monika Rathert, and Arnim von Stechow. New York, NY: Walter de Gruyter, pp. 153-204. ISBN: 9783110172294. [Preview in Google Books]
von Fintel, Kai, and Sabine Iatridou. "Since Since." Working paper, Massachusetts Institute of Technology, March 2005. (PDF)
De Re and De Dicto
"DPs (Determiner Phrases) and Scope in Modal Contexts." Chapter 7 in [Intensional Semantics].
The Third Reading
"Beyond de re—de dicto: The Third Reading." Chapter 8 in [Intensional Semantics].
Percus, Orin. "Constraints on Some Other Variables in Syntax." Natural Language Semantics 8, no. 3 (September 2000): 173-229.
Schwager, Magdalena. "Speaking of Qualities." Paper presentation, Semantics and Linguistic Theory (SALT) 19 Conference, Ohio State University, Columbus, OH, April 3-5, 2009. Slides (PDF - 1.0MB) (Courtesy of J. Magdalena Schwager. Used with permission.) Paper (PDF) (Courtesy of J. Magdalena Schwager. Used with permission.)
Keshet, Ezra. "Split Intensionality: A New Scope Theory of De re and De dicto." Working paper, University of Michigan, Ann Arbor, May 2009.